For example, in an automobile assembly line, a work of assembling an engine and a door, etc., to a vehicle body transported while being suspended from a hanger provided on a traveling body of a trolley conveyor or a self-propelled train is performed, and in this case, it is known that such a work of assembling parts to a vehicle body supported by the hanger is performed on a carriage of a carriage-type transportation device. As a transportation facility available in this case, for example, as described in Patent Document 1 (defined below), a transportation facility is known in which a traveling body (traveling body of a trolley conveyor driven by a pusher) having a hanger for supporting a vehicle body is made to travel in synch with a transportation device on the floor side and a work of assembling parts to the vehicle body transported from a position on the transportation device on the floor side while being suspended from the hanger, and as described in Patent Document 2, a transportation facility is known in which an object transported while being suspended from a hanger is transferred onto a carriage of a carriage-type transportation device that travels in synch with a traveling body of a trolley conveyer or a self-propelled train having this hanger, and after finishing a work on the carriage, the vehicle body on the carriage is returned to the hanger again.    Patent document 1: Japanese Published Examined Patent Application No. H04-5581.    Patent document 2: Japanese Published Unexamined Patent Application No. H07-157073.